This will be a broad base study involving patients and laboratory investigations on external ocular disease. The nature of virus infections of the cornea, virus chemotherapy, corneal preservation, corneal morphology, and the suppression of immune reactions will be studied both in the laboratory and in patients. BIBLIOGRAPHIC REFERENCES: Kaufman, H.E., Mudd, S., Varnell, E.D., and Engelstein, J.: Effect of non specific immune stimulation on the recurrence rate of herpetic keratitis in rabbits. Invest. Ophth. 14:469, 1975; Abel, R., Jr., Kaufman, H.E. and Sugar, J.: Effect of intravenous adenine arabinoside against herpes simplex keratouveitis in humans. Amer. J. Ophth. 79:659, 1975.